The potential effect of a Brexit on the NHS has become a key political battleground with wildly divergent statistics being quoted and outlandish claims being made by both campaigns. Should the UK vote to leave the EU on 23 June there are a number of potential impacts on the NHS, outlined below.

Funding

The Leave campaign has repeatedly argued that leaving the EU will save money which can be diverted towards NHS funding. The Institute for Fiscal Studies (IFS" has calculated that the net UK contribution to the EU over the next few years will be approximately £8bn a year. However, this is balanced by the potential risks to the economy that a Brexit poses – a negative effect of just 0.6% on national income would cancel out any saving.

So whilst there is the potential for greater funding of the NHS after a leave vote, it is a gamble. It is also important to remember that it is up to the Government how any saving would be spent – and there is no guarantee that the funds would be diverted to the NHS budget.

Demand

It is clear that an increased population means increased demands on the health service. Pro- Leave campaigners have suggested that remaining in the EU will lead to increased migration and demands on the NHS (noting that a number of countries could possibly join the EU in the near future).

Under the Vienna Convention, any EU citizen currently residing in the UK will be entitled to stay, regardless of a Brexit. Therefore the population currently entitled to use the NHS will not reduce, but a Brexit may stop any increase caused by migration, thereby creating a cost saving.

Staffing / Recruitment

Meanwhile, 130,000 non-British Europeans work in the NHS, making up around 10% of NHS doctors and 4% of nurses. As noted above, under the Vienna Convention, these individuals are entitled to stay in the UK, so there is unlikely to be an immediate staffing crisis.

However, the EU's single-market rules provide the legal basis for laws on recognition of professional qualifications – meaning healthcare staff can work anywhere in Europe. Leaving the EU will mean the UK no longer benefits from this cross-country recognition and so it will be harder to recruit overseas staff to work in the NHS.

Reciprocal treatment arrangements

Whilst part of the EU, the UK benefits from reciprocal treatment arrangements, whereby it is able to reclaim the costs spent treating EU nationals in the UK (and other EU countries can reclaim their costs from the UK).

If we were to leave the EU some kind of reciprocal arrangement would need to be negotiated, which would mean setting up and agreeing a system of charges with each country. Whilst this is achievable, it may take some time to organise, and lead to delays or increased administrative pressures on healthcare staff.

Research Funding

Currently, the UK is the largest beneficiary of EU funding for health research; the Horizon 2020 programme, for example, invested £232m into NHS providers in 2014/2015. A leave vote would not necessarily mean the NHS would no longer benefit from cross-country research programmes and cooperation, but parting ways with the EU would almost certainly mean saying goodbye to a significant portion of the research funding the NHS currently receives.